1. Field of the Invention
The present invention relates to new arylene compounds having polypenylene group and polymers thereof, which can be used as an organic or polymeric semi-conducting material or a optoelectronic material, and especially, as a electroluminescence (hereinafter, referred to as “EL”) material, to a method for preparing the same, and to an EL element using the same.
2. Description of the Related Art
Generally, polymers of poly(phenylene vinylene) (hereinafter, referred to as “PPV”), of polythiophene (hereinafter, referred to as “PTh”) and of polyphenylene (See Synth. Met., 50 (1–3), p. 491 (1992); Adv. Mater., 4, p. 36 (1992); Adv. Mater., 6, p. 190 (1994); and Chem. Rev., 99, p. 1747 (1999)) are known as organic polymer semiconductor and optoelectronic materials (See Semiconducting Polymers: Chemistry, Physics and Engineering, edited by G. Hadziioannou; and P. F. van Hutten, WILEY-VCH (2000)) or as materials for polymer luminescence (See Angew Chem. Int. Ed., 37, p. 402 (1998); Nature, 397, p. 121 (1999); Prog. Polym. Sci., 25, p. 1089 (2000); and Adv. Mater., 12, p. 1737 (2000)). Until now, researches into these polymer materials have been conducted, but such materials have disadvantages in that final products are not dissolved in an organic solvent. PPV or PTh derivatives, which are improved their processability by introducing appropriate substituents and illuminate light of blue, green or red color, have also been known (See Synth. Met., 62, p. 35 (1994); Adv. Mater., 4, p. 36 (1992); and Macromolecules, 28, p. 7525 (1995)). Some of them have been known to have excellent processability because they are soluble in an organic solvent in spite of their large molecular weight (See Adv. Mater., 10, p1340 (1998)).
Recently, a lot of fluorene-based polymers have been reported as luminescence materials (See Jpn. J. Appl. Phys., 30, pL1941 (1991); J. Polym. Sci. Polym. Chem. Ed., 31, p. 2465 (1993); J. Am. Chem. Soc., 118, 7416 (1996); Adv. Mater., 9, p. 326 (1997); Adv. Mater., 10, p. 993 (1998); Macromolecules, 32, p. 1476 (1999); Nature, 405, p. 661 (2000); Syn. Met., 111–112, p. 397 (2000); Syn. Met., 122, p. 79 (2001) and J. Am. Chem. Soc., 123, 946 (2001)).
In addition, the U.S. Pat. Nos. 5,621,131; 5,708,130; and 5,900,327 disclose fluorene-based polymers having single bonds and the U.S. Pat. No. 5,807,974 discloses fluorene-based alternating copolymers having conjugate double bonds, which are luminescent materials for an EL element.
Polymers having acetylene groups have also been reported as organic polymer semiconductor and photo-electronic materials (See Macromol. Chem., 191, p. 857 (1990); Macromolecules, 27, p. 562 (1994); J. Chem. Soc., Chem. Commun., p. 1433 (1995); and Macromolecules, 29, p. 5157 (1996)), which are mainly materials for nonlinear optics, photoconductivity or photoluminescence (hereinafter, referred to as “PL”). Syn. Met., 102, p933 (1999) is an example of using these polymers as an EL material, and other applications have been also reported (See Science, 279, p. 835 (1998)).
In addition, polymers having diacetylene groups have been reported (See Prog. Polym. Sci., 20, p. 943 (1995); CHEMTECH, October, p. 32 (1993)); Macromolecules, 29, p. 2885 (1996); Syn. Met., 111–112, p. 429 (2000); and Syn. Met., 119, p. 105 (2001). These polymers are as sensitive to heat or light as the acetylene group polymers, and therefore, they can be easily cross-linked, to give stable cross-linked polymers. An example of applying polymers having acetylene or diacetylene groups for EL materials has patented by the present inventors (the U.S. Pat. No. 5,876,864 and the Japanese Patent No. 3,046,814). These polymers can also be applied for materials of nonlinear optics, heat resistant polymers, polarized PL polymers, and electrically or optically active polymers.
Meanwhile, polyphenylene group polymers having a plurality of phenyl groups (See J. Polym. Sci., Part B, 4, p. 791 (1966); J. Polym. Sci., Part A-1, 5, p. 2721 (1967); J. Polym. Sci., Part B, 7, p. 519 (1969); Macromolecules, 5, p. 49 (1972); Macromolecules, 28, p. 124 (1995); Macromolecules, 33, p. 3525 (2000)) can be obtained by Diels-Alder reaction between a compound having a bis(acetylene) group and a compound having a bis(cyclopentadienone) group (See J. Org. Chem., 28, p. 2725 (1963); Chem. Rev., 65, p. 261 (1965); J. Org. Chem., 30, p. 3354 (1965); and the U.S. Pat. No. 4,400,540). This is a polymerization reaction that a molecular weight is increased while carbon monoxide is removed. This polymerization is carried out at 100° C.–400° C. without a solvent, or with a solvent selected from toluene, diphenyl ether, o-diclorobenzene and cyclohexylbenzene, by which a polymer is obtained in high yield of more than 80%. Since the obtained polymers have several phenyl groups, they are thermally stable and easily dissolved in an organic solvent while having high molecular weight. Accordingly, such polymers can be applied as a photoreceptor (See the U.S. Pat. No. 5,882,829), or as a dielectric substance in microelectronics industry, especially, in the field of integrated circuits (See the U.S. Pat. No. 5,965,679). Polyphenylene group polymers can be also obtained by Eidls-Alder reaction of bis(α-pyrone)s or bis(thiophene dioxide)s, instead of bis(cyclopentadienone) (See J. Chem. Soc. Perkin Trans 1 p. 355 (1994); and the U.S. Pat. Nos. 2,971,944 and 2,890,207).
However, in the case of the aforementioned monomers, that is, bis(acetylene) compounds or bis(cyclopentadienone) compounds, costs for preparing are high, or preparing procedures are difficult, and therefore, various kinds of such monomers have not been provided. Especially, in the case of the bis(cyclopentadienone) compounds, its kind is so limited that polyphenylene group polymers having various properties and structures can not be prepared.